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Former US energy secretary Dan Brouillette, who served during the first Trump administration, says a US export ban on diesel is unlikely to reduce prices long-term.

While it might temporarily push down US diesel prices, Brouillette tells Radio 4's Today programme that the US refines "more than we actually consume" which means "storage becomes an issue".

"When you reach that limit, what happens in the refining business is you begin to shut down the…refining production," he says. This means that, "over a period of time, prices will continue to rise again".

Brouillette goes on to explain other knock-on effects, saying that if one country leads with an export ban, "you can pretty well expect" others to follow suit.

Francisco Velasquez
Business reporter

Image source, Getty Images

For the US economy, a ban could deliver short-term relief at the pump by flooding the domestic market with excess supply.

However, energy analysts warn it could backfire.

David Fyfe, chief economist at Argus Media, notes that cutting off American supply would likely cause international prices to skyrocket.

That would push up global freight, food, and industrial costs, ultimately "feeding inflation back into the global economy".

"At a stroke, the US's reputation as a reliable supplier of energy to the world would be shot," Fyfe adds.

Removing more than a million barrels of daily American supply would trigger a fierce bidding war among importing nations in Latin America and Europe.

Sarah Raffoul, analytics manager at Argus Media, notes that while higher international prices would eventually curb demand, the immediate gap would severely strain trade relationships and accelerate global inflation.

• Read more from our business reporter here

James FitzGerald
North America reporter

Image source, Reuters

The American pressure on Europe over diesel supplies can be seen within the context of next month's US midterm elections, during which members of Congress will be elected.

The vote takes place on 3 November and could have a major impact on the rest of President Donald Trump’s time in the White House.

Ahead of the poll, the condition of the American economy is on the minds of many voters, as many of them have been struggling with the price of fuel, groceries, housing and healthcare.

Inflation in the US remains above the level targeted by the US Federal Reserve, partly due to the war that the US and Israel started with Iran in February.

Prices of petrol and diesel globally have skyrocketed since the war's outbreak - and Americans have not been insulated from the shock.

Diesel prices specifically hit a record high of more than $6.50 (£4.87) a gallon at one point last month, according to American Automobile Association data.

Members of Trump's Republican Party have been ramping up pressure on the president to curb diesel exports, believing this could ease the situation for American consumers whose votes they want to court.

Javier Blas, an energy columnist at Bloomberg, tells Radio 4's Today programme that American pressure has been "very intense".

"The US needed a quid pro quo and they created it," he says, in reference to President Donald Trump's suggestion that he is considering banning US diesel exports. The president may also ask European countries to release some of their reserves.

"Certainly there is scarcity" at the moment and it could get "much worse" if the US does enact an export ban, Blas says.

Asked how much of their reserves it would be "sensible" for European countries to release, Blas says he doesn't think Europe should release more than "one third".

Scarcity is not just due to the conflict in the Middle East, he says, adding that it has been "exacerbated" by the export ban on Russia and Ukrainian attacks on Russian refineries.

Releasing more than half of their reserves would leave European countries "very vulnerable" if global conflicts get worse over the coming months, Blas says.

Diesel prices hit an all-time high of 199.33p per litre earlier this week, the RAC motoring organisation announced, as the war in the Middle East continues to push up the cost of fuel.

The RAC said on Monday that diesel prices had entered "uncharted territory" and served as a reminder of "just how exposed the UK is to events occurring far away".

The cost of diesel rose by 59p a litre, or just under 40%, since the US-Israel conflict with Iran erupted at the end of February. The previous record was 199.09p in June 2022 following Russia's full-scale invasion of Ukraine.

The RAC will release updated figures later this morning, we'll bring you those as soon as we have them.

The UK is among European countries facing American pressure to release some of their diesel reserves, as the Iran war puts pressure on supply.

US President Donald Trump has threatened to restrict diesel exports, and US Treasury Secretary Scott Bessent argues that US farmers, truckers, and businesses "should not be left carrying the burden" as prices soar.

Over half of the UK's diesel is imported, with 31% of the imports coming from the US.

Diesel prices in the UK hit record highs this week and are hovering just under 200p per litre, according to motoring organisation the RAC - which will release updated figures later this morning.

European ministers have been meeting in Brussels to discuss the potential ban, with France proposing that European countries release 50 million barrels of diesel.

Stay with us as we bring you the latest developments.